Field of the Invention
The invention provides pepper plants having Powdery mildew fungal resistance and methods for obtaining such pepper plants.
Description of Related Art
Peppers are one of the most popular fruit-bearing plants grown worldwide. Pepper plants are grown in a wide range of climates, in open fields as well as in greenhouses. Peppers belong to the genus Capsicum, of the nightshade family, Solanaceae (e.g. Capsicum annuum). The term “pepper” may refer to the plant as well as its fruit. Peppers are commonly broken down into three groupings: bell peppers, sweet peppers, and hot peppers. Most popular pepper varieties fall into one of these categories, or as a cross between them. However, these groupings are not absolute, as both “hot pepper” and “sweet pepper” encompass members belonging to several different species. Additionally, members of each of the groups may be different cultivars of the same species. For example, the bell pepper, the jalapeno pepper, and the “That sweet” all belong to the species Capsicum annuum L. Hot peppers, including some inedible varieties, are grown for edible as well as ornamental and medicinal uses. While there are pungent (i.e. “hot”) varieties of C. annuum, many well known hot peppers are members of different species. For example, both the cayenne pepper and the Tabasco pepper are varieties of Capsicum frutescens, while the hottest peppers, including the habanero and naga varieties, are members of Capsicum chinense. 
Pepper breeding efforts have focused in part on growing pepper plants resistant to diseases such as Powdery Mildew (PM), caused by the fungus Leveillula taurica. Powdery mildew caused by the fungus Leveillula taurica exhibits a worldwide disease distribution and may affect peppers grown under greenhouse or field conditions.
Symptoms of pepper Powdery Mildew caused by the fungus Leveillula taurica during the initial stages of infection may include visible light-green to bright-yellow blotches appearing on upper and lower surfaces of leaves followed by a powdery, white growth caused by the sporulation of the fungus. Under some environmental conditions these areas may later turn necrotic. Infected leaves may also curl upward and exhibit a visible powdery, white growth on the underside of leaves. When lesions are numerous, they often coalesce, resulting in general chlorosis and leaf drop. The disease generally progresses from older to younger leaves. Common commercial fruit production yield losses come from fruits on affected plants being overexposed to sunlight and developing sunscald as well as reduced yield due to leaf loss.
Airborne conidia (asexual fungal spores) from previously infected crops or weeds can be carried long distances by wind and act as initial sources of inoculum. The wide host range of these fungi exacerbate disease spread and reduce the ability of agronomic practice to control disease incidence. Disease control is commonly managed by application of fungicides before infection or immediately after the first symptoms are observed. In addition to the cost of pesticide application, there is increasing social pressure to reduce the pesticide load in the environment.
There is a need for pepper varieties having resistance to Powdery Mildew (PM), caused by the fungus Leveillula taurica. 